/**
  * Return attached files but filter the private ones if user is not a member 
  * of the owner company
  *
  * @param void
  * @return array
  */
 function getAttachedFiles()
 {
     if (logged_user()->isMemberOfOwnerCompany()) {
         return $this->getAllAttachedFiles();
     }
     // if
     if (is_null($this->attached_files)) {
         $this->attached_files = AttachedFiles::getFilesByObject($this, true);
     }
     // if
     return $this->attached_files;
 }